Process for producing an organic compound

ABSTRACT

Process for producing a chlorohydrin by reaction between a multihydroxylated-aliphatic hydrocarbon, an ester of a multihydroxylated-aliphatic hydrocarbon, or a mixture thereof, and a chlorinating agent, according to which the multihydroxylated-aliphatic hydrocarbon, the ester of a multihydroxylated-aliphatic hydrocarbon, or the mixture thereof used contains at least one solid or dissolved metal salt, the process comprising a separation operation to remove at least part of the metal salt.

The present patent application is a continuation of U.S. applicationSer. No. 11/915,059, filed Nov. 20, 2007, now allowed, incorporatedherein by reference; which is a 371 of PCT/EP2006/062438 371 filed May19, 2006. This application also claims benefit of patent application FR05.05120 and patent application EP 05104321.4, both filed on May 20,2005 and of U.S. Provisional Patent Applications 60/734,659, 60/734,627,60/734,657, 60/734,658, 60/734,635, 60/734,634, 60/734,637 and60/734,636, all filed on Nov. 8, 2005, the contents of which areincorporated herein by reference.

The present invention relates to processes for producing an organiccompound, in particular to a process for producing a chlorohydrin.

It is known that natural petrochemical resources, for example oil ornatural gas, that are available on earth are limited. Now, theseresources are used for producing fuels and as a starting product forproducing a large variety of useful organic compounds such as monomersor reactants for producing plastics, for example, ethylene oxide andchloroethanol (see for example K. Weissermel and H.-J. Arpe inIndustrial Organic Chemistry, Third Completely Revised Edition, VCHEditor, 1997, page 149), propylene oxide and monochloropropanol (see forexample K. Weissermel and H.-J. Arpe in Industrial Organic Chemistry,Third Completely Revised Edition, VCH Editor, 1997, page 275),epichlorohydrin or dichloropropanol (see, for example, Ullmann'sEncyclopedia of Industrial Chemistry, 5. ed., Vol. A9, p. 539-540).Documents Chemistry and Industry, Nov. 20, 1931, Part III, pages 949 to954, and Nov. 27, 1931, Part III, pages 970 to 975, describe a processfor the synthesis of dichloropropanol from glycerol and hydrochloricacid in the presence of acetic acid as acid catalyst.

According to known processes for producing chlorohydrins, the product isgenerally obtained in highly diluted aqueous solution with a titre of 5to 15% by weight. It is then particularly expensive to purify it.Moreover, in the case of dichloropropanol, the major isomer obtainedaccording to such processes is 2,3-dichloropropane-1-ol.

It was desirable to find uses and processes making it possible to reducethe consumption of natural petrochemical resources, in particular forthe abovementioned uses.

It was also desirable to find processes for re-using by-products ofother production processes so as to minimize the overall amount ofby-products having to be eliminated or destroyed.

It was also desirable to find processes for minimizing the cost ofseparation operations linked to highly diluted aqueous solutions.

Consequently, the invention relates to a process for producing achlorohydrin by reaction between a multihydroxylated-aliphatichydrocarbon, an ester of a multihydroxylated-aliphatic hydrocarbon, or amixture thereof, and a chlorinating agent, according to which themultihydroxylated-aliphatic hydrocarbon, the ester of amultihydroxylated-aliphatic hydrocarbon, or the mixture thereof usedcontains at least one solid or dissolved metal salt, the processcomprising a separation operation to remove at least part of the metalsalt.

The term “multihydroxylated-aliphatic hydrocarbon” refers to ahydrocarbon which contains at least two hydroxyl groups attached toseparate saturated carbon atoms. The multihydroxylated-aliphatichydrocarbon may contain, but not to be limited thereby, from 2 to 60carbon atoms.

Any single carbon of a multihydroxylated-aliphatic hydrocarbon bearingthe hydroxyl (OH) functional group must possess no more than one OHgroup, and must be sp3 hybridized. The carbon atom bearing the OH groupmay be primary, secondary or tertiary. The multihydroxylated-aliphatichydrocarbon used in the present invention must contain at least two sp3hybridized carbons each bearing an OH group. Themultihydroxylated-aliphatic hydrocarbon includes any vicinal-diol(1,2-diol) or triol (1,2,3-triol) containing hydrocarbon includinghigher orders of contiguous or vicinal repeating units. The definitionof multihydroxylated-aliphatic hydrocarbon also includes for example oneor more 1,3-, 1,4-, 1,5- and 1,6-diol functional groups as well. Themultihydroxylated-aliphatic hydrocarbon may also be a polymer such aspolyvinylalcohol. Geminal-diols, for example, would be precluded fromthis class of multihydroxylated-aliphatic hydrocarbon compounds.

It is to be understood that the multihydroxylated-aliphatic hydrocarboncan contain aromatic moieties or heteroatoms including for examplehalide, sulfur, phosphorus, nitrogen, oxygen, silicon and boronheteroatoms, and mixtures thereof.

Multihydroxylated-aliphatic hydrocarbons useful in the present inventioninclude for example 1,2-ethanediol (ethylene glycol), 1,2-propanediol(propylene glycol), 1,3-propanediol, 1-chloro-2,3-propanediol(chloropropanediol), 2-chloro-1,3-propanediol (chloropropanediol),1,4-butanediol, 1,5-pentanediol, cyclohexanediols, 1,2-butanediol,1,2-cyclohexanedimethanol, le 1,2,3-propanetriol (also known asglycerol, glycerin or glycerine), and mixtures thereof. Preferably, themultihydroxylated-aliphatic hydrocarbons used in the present inventioninclude for example 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol,1,2,3-propanetriol and mixtures thereof. More preferably, themultihydroxylated-aliphatic hydrocarbons used in the present inventioninclude for example 1,2-ethanediol, 1,2-propanediol, chloropropanediol,1,2,3-propanetriol and any mixture thereof. 1,2,3-propanetriol is themost preferred.

Esters of multihydroxylated-aliphatic hydrocarbon can be present in themultihydroxylated-aliphatic hydrocarbons and/or can be produced in theprocess for producing the chlorohydrin according to the invention and/orcan be manufactured prior to the process for producing the chlorohydrin.Examples of esters of multihydroxylated-aliphatic hydrocarbon are ethyleglycol mono acetate, propanediol monoacetates, glycerol monoacetates,glycerol monosterates, glycerol diacetates and their mixtures.

The term “chlorohydrins” refers to a compound containing at least onehydroxyl group and at least one chlorine atom attached to separatesaturated carbon atoms. A chlorohydrin that contains at least twohydroxyl groups is also a multi-hydroxylated aliphatic hydrocarbon.Accordingly, the starting material and product of the present inventioncan each be chlorohydrins. In that case, the product chlorohydrin ismore highly chlorinated than the starting chlorohydrin, i.i., has morechlorine atoms and fewer hydroxyl groups than the starting chlorohydrin.Preferred chlorohydrins are for example chloroethanol, chloropropanol,chloropropanediol and dichloropropanol, with dichloropropanol being themost preferred. Particularly preferred chlorohydrins are2-chloroethanol, 1-chloropropane-2-ol, 2-chloropropane-1-ol,1-chloropropane-2,3-diol, 2-chloropropane-1,3-diol,1,3-dichloropropane-2-ol and 2,3-dichloropropane-1-ol and any mixturethereof.

The multihydroxylated-aliphatic hydrocarbon can be a syntheticmultihydroxylated-aliphatic hydrocarbon, a multihydroxylated-aliphatichydrocarbon obtained from renewable raw materials or a mixture thereof.Preferably, the multihydroxylated-aliphatic hydrocarbon used in theprocess of the invention has at least partially been produced fromrenewable raw materials. The same considerations apply to the ester of amultihydroxylated-aliphatic hydrocarbon, or the mixture of the ester ofa multihydroxylated-aliphatic hydrocarbon and themultihydroxylated-aliphatic hydrocarbon.

The expression

synthetic

means that the multihydroxylated-aliphatic hydrocarbon has been obtainedfrom fossil raw materials. By fossil raw materials, one intends todenote materials derived from natural petrochemical feedstock, like forinstance, petroleum, natural gas, and coal. Among those raw materials,organic compounds including 2 and 3 carbon atoms are preferred. When thechlororhydrin is dichloropropanol or chloropropanediol, allyl chloride,allyl alcohol and “synthetic” glycerol are more preferred. By“synthetic” glycerol, one intends to denote a glycerol obtained frompetrochemical feedstocks. When the chlorohydrin is chloroethanol,ethylene and “synthetic” ethylene glycol are more preferred. By“synthetic” ethylene glycol, one intends to denote an ethylene glycolobtained from petrochemical feedstocks. When the chlorohydrin ischloropropanol, propylene and “synthetic” propylene glycol are morepreferred. By “synthetic” propylene glycol, one intends to denote apropylene glycol obtained from petrochemical feedstocks. The sameconsiderations apply to the ester of a multihydroxylated-aliphatichydrocarbon, or the mixture of the ester of amultihydroxylated-aliphatic hydrocarbon and themultihydroxylated-aliphatic hydrocarbon.

By renewable raw materials, one intends to denote materials obtainedfrom the treatment of renewable raw materials. Among those materials,natural ethylene glycol, natural propylene glycol and natural glycerolare preferred. “Natural” ethylene glycol, propylene glycol and glycerolcan be obtained for instance by thermochemical conversion of sugarsderived from biomass treatments as described in “Industrial Bioproducts:Today and Tomorrow, Energetics, Incorporated for the U.S. Department ofEnergy, Office of Energy Efficiency and Renewable Energy, Office of theBiomass Program, July 2003, pages 49, 52 to 56”. One process is forexample the catalytic hydrogenolysis of sorbitol obtained bythermochemical conversion of glucose. Another process is for example thecatalytic hydrogenolysis of xylitol obtained by hydrogenation of xylose.Xylose can for example be obtained by hydrolysis of hemicellulosecontained in corn fibers.

The expression “glycerol obtained from renewable raw materials” or“natural glycerol” is intended to denote in particular glycerol obtainedin the course of the production of biodiesel, or else glycerol obtainedduring conversions of fats or oils of plant or animal origin in general,such as saponification, trans-esterification or hydrolysis reactions.

Among oils usable in the process of the invention, one can quote allcurrent oils, like the corn, sunflower, old or new colza, babassu,copra, cabbage tree, palm oils, of ricinus and cotton, groundnut oils,soya, flax and crambe and all oils resulting for example from the plantsof sunflower or colza obtained by genetic modification or hybridization.One can even use worn oils of crackling, varied animal oils, like fishoils, tallow, the lard and even of greases of squaring. Among oils used,one can still indicate the oils partially modified for example bypolymerization or oligomerization such as for example “linseed oil standoils”, sunflower and puffed up vegetable oil.

A particularly suitable glycerol can be obtained during the conversionof animal fats. Another particularly suitable glycerol can be obtainedduring the production of biodiesel. Another yet particularly suitableglycerol can be obtained during the conversion of fats or oils of plantor animal origin, by transesterification in the presence of anheterogeneous catalyst, such as described in documents FR 2752242, FR2869612 and FR 2869613. More specifically, the heterogeneous catalyst isselected from mixed oxides of aluminium and zinc, mixed oxides of zincand titanium, mixed oxides of zinc, titanium and aluminium, and mixedoxides of bismuth and aluminium, and the heterogeneous catalyst is usedin a fixed-bed configuration. In the process according to the invention,glycerol can be as described in the patent application entitled<<Process for preparing a chlorohydrin by conversion ofmulti-hydroxylated aliphatic hydrocarbons” filed in the name of SOLVAYSA on the same day as the present application, the contents of which areincorporated herein by reference.

Mention is particularly made of a process for manufacturing achlorohydrin, wherein a multi-hydroxylated aliphatic hydrocarbon, anester of a multi-hydroxylated aliphatic hydrocarbon, or a mixturethereof, the total metal content of which expressed as elements ishigher than or equal to 0.1 μg/kg and lower than or equal to 1 000mg/kg, is submitted to a reaction with a chlorinating agent.

In contrast, “synthetic multihydroxylated-aliphatic hydrocarbon” isgenerally obtained from petrochemical resources. The same considerationsapply to the ester of a multihydroxylated-aliphatic hydrocarbon, or themixture of the ester of a multihydroxylated-aliphatic hydrocarbon andthe multihydroxylated-aliphatic hydrocarbon.

In the process according to the invention, themultihydroxylated-aliphatic hydrocarbon used can be a crudemultihydroxylated-aliphatic hydrocarbon product or a purifiedmultihydroxylated-aliphatic hydrocarbon product. A “crude”multihydroxylated-aliphatic hydrocarbon product is amultihydroxylated-aliphatic hydrocarbon which has not been submitted toany treatment after its manufacture. A “purified”multihydroxylated-aliphatic hydrocarbon product is amultihydroxylated-aliphatic hydrocarbon which has been submitted to atleast one treatment after its manufacture. When themultihydroxylated-aliphatic hydrocarbon is a crude product obtained fromrenewable raw materials, it can comprise, for example, water in additionto a metal salt. The metal salt is in particular a metal chloride, whichis preferably chosen from NaCl and KCl. The metal salt can also beselected from metal sulphates such as sodium sulphate and potassiumsulfate. The multihydroxylated-aliphatic hydrocarbon used in the processaccording to the invention contains at least one solid or dissolvedmetal salt which is preferably selected from sodium chloride, potassiumchloride, sodium sulfate and potassium sulfate. Themultihydroxylated-aliphatic hydrocarbon used in the process according tothe invention has generally a metal salt content of at least 0.5% byweight, preferably greater than or equal to approximately 1% by weight,more preferably greater than or equal to approximately 2% by weight,most preferably greater than or equal to approximately 3% by weight. Themetal salt content is generally of at most 15% by weight, preferablyless than or equal to 10% by weight, more preferably less than or equalto approximately 7.5% by weight and most preferably less than or equalto 5% by weight. The same considerations apply to the ester of amultihydroxylated-aliphatic hydrocarbon, or the mixture of the ester ofa multihydroxylated-aliphatic hydrocarbon and themultihydroxylated-aliphatic hydrocarbon.

In the process according to the invention, the crudemultihydroxylated-aliphatic hydrocarbon product can also contain organicimpurities such as carbonyl compounds, in particular aldehydes, fattyacids, salts of fatty acids or esters of fatty acids, such as inparticular mono- or polyesters of the multihydroxylated-aliphatichydrocarbon with fatty acid, optionally in combination with water. Whenthe multihydroxylated-aliphatic hydrocarbon is glycerol, preferred fattyacids are saturated and unsaturated fatty acids containing more than 12carbon atoms like for instance oleic, linoleic and linolenic acids.Those acids are for instance produced during the conversion of colza oilby saponification, trans-esterification and hydrolysis reactions.Preferred esters of fatty acids are methylic esters.

In the process according to the invention, the crude product generallycomprises at most 10% by weight of organic impurities, often 8% byweight of organic impurities. Often, the crude product comprises at most6% by weight of organic impurities. Preferably, it comprises at most 2%by weight of organic impurities. Most preferably, it comprises at most1% by weight of organic impurities. The organic impurities typicallyconsist essentially of fatty acids and their derivatives.

The invention then also relates to a process for producing achlorohydrin according to which a multihydroxylated-aliphatichydrocarbon, an ester of a multihydroxylated-aliphatic hydrocarbon, or amixture thereof, containing at most 8% by weight of organic impuritiesis subjected to a reaction with a chlorinating agent.

It has surprisingly been found that the use of crude product having ahigh content of organic impurities does not have substantial impact onthe reaction underlying the process of the invention. Optionalbyproducts from the organic impurities can easily be eliminated from thereaction mixture e.g., if applicable, by controlling the purge rate asdescribed in the patent application WO 2005/054167 in the name of SOLVAYSA, the content of which is incorporated herein by reference, from page17, line 33 to page 18, line 2, from page 24, lines 8 to page 25, line10.

In the process according to the invention, the crudemultihydroxylated-aliphatic hydrocarbon product generally comprises atleast 40% by weight of the multihydroxylated-aliphatic hydrocarbon.Often, the crude product comprises at least 50% by weight of themultihydroxylated-aliphatic hydrocarbon. Preferably, it comprises atleast 70% by weight of the multihydroxylated-aliphatic hydrocarbon.Often, the crude product comprises at most 99% by weight of themultihydroxylated-aliphatic hydrocarbon. Typically, it comprises at most95% by weight of the multihydroxylated-aliphatic hydrocarbon.

In the process according to the invention, the crudemultihydroxylated-aliphatic hydrocarbon product generally comprises atleast 5% by weight of water or, in the absence of other compounds thanwater and the multihydroxylated-aliphatic hydrocarbon, at least 1% byweight of water. In the process according to the invention, the crudemultihydroxylated-aliphatic hydrocarbon product generally comprises atmost 50% by weight of water or, in the absence of other compounds otherthan water and the multihydroxylated-aliphatic hydrocarbon, at most 60%by weight of water. Often, the crude multihydroxylated-aliphatichydrocarbon product comprises at most 30% by weight of water, preferablyat most 21% by weight of water.

In another embodiment, the crude multihydroxylated-aliphatic hydrocarbonproduct comprises at most 89% by weight of themultihydroxylated-aliphatic hydrocarbon. In that embodiment, the crudemultihydroxylated-aliphatic hydrocarbon product comprises at most 85% byweight of the multihydroxylated-aliphatic hydrocarbon. In thatembodiment, the crude multihydroxylated-aliphatic hydrocarbon productcomprises generally at least 10% by weight of water and often at least14% by weight of water.

The crude multihydroxylated-aliphatic hydrocarbon product has a metalsalt content of at least 0.5% by weight, preferably greater than orequal to approximately 1% by weight and more preferably greater than orequal to approximately 1.5% by weight. The crudemultihydroxylated-aliphatic hydrocarbon has a metal salt content of atmost 15% by weight, preferably less than or equal to 12% by weight andmore preferably less than or equal to approximately 7.5% by weight.

The separation operation according to the invention applies particularlypreferably to the production of chlorinated compounds starting from amultihydroxylated-aliphatic hydrocarbon, especially to the production ofchlorohydrins and epoxides. Surprisingly, the separation operationaccording to the invention makes it possible to economically obtainthese compounds starting from renewable resources.

The term

epoxide

is used to describe a compound containing at least one oxygen bridge ona carbon-carbon bond. Generally, the carbon atoms of the carbon-carbonbond are contiguous and the compound can include other atoms than carbonand oxygen atoms, like hydrogen and halogens, for example. Preferredepoxides are ethylene oxide, propylene oxide, glycidol andepichlorohydrin.

Consequently, the invention also relates in particular to a process forproducing a chlorinated organic compound, according to which amultihydroxylated-aliphatic hydrocarbon, an ester of amultihydroxylated-aliphatic hydrocarbon, or a mixture thereof, obtainedfrom renewable raw materials is used, and themultihydroxylated-aliphatic hydrocarbon, the ester of amultihydroxylated-aliphatic hydrocarbon, or the mixture thereof, usedcontains at least one solid or dissolved metal salt and the processcomprises a separation operation to remove at least part of the metalsalt. It is understood that the methods of production describedhereinafter can also be carried out with multihydroxylated-aliphatichydrocarbons, esters of a multihydroxylated-aliphatic hydrocarbon, ormixtures of esters of a multihydroxylated-aliphatic hydrocarbon andmultihydroxylated-aliphatic hydrocarbons in general and are not limitedto the preferred use of a multihydroxylated-aliphatic hydrocarbon,esters of a multihydroxylated-aliphatic hydrocarbon, or mixtures thereofobtained from renewable raw materials.

In the following, the expression “chlorinated compound” has to beunderstood as “chlorohydrin”. Preferred chlorohydrins are for examplechloroethanol, chloropropanol, chloropropanediol and dichloropropanol,with dichloropropanol being the most preferred.

The term “chloroethanol” is intended to mean a mixture comprising2-chloroethanol.

The term “chloropropanol” is intended to mean a mixture of isomerscomprising 1-chloropropane-2-ol and 2-chloropropane-1-ol.

The term “chloropropanediol” is intended to mean a mixture of isomerscomprising 1-chloropropane-2,3-diol and 2-chloropropane-1,3-diol.

The term “dichloropropanol” is intended to mean a mixture of isomerscomprising 1,3-dichloropropane-2-ol and 2,3-dichloro-propane-1-ol.

In the process for producing a chlorohydrin according to the invention,the chlorinating agent can be hydrogen chloride and/or hydrochloricacidic as disclosed in the patent application WO 2005/054167 of SOLVAYSA, from page 4, line 30 to page 6, line 2. Mention can particularly bemade a chlorinating agent which can be gaseous hydrogen chloride,aqueous solution of hydrogen chloride or combination of both. Hydrogenchloride can arise from a pyrolysis process of chlorinated organiccompounds as for example, a production of vinyl chloride, a productionof 4,4-methylenediphenyl diisocyanate (MDI) or toluene diisocyanate, orfrom processes for cleansing metals or by reaction of inorganic acidssuch as sulphuric acid or phosphoric acid on metal chlorides such assodium chloride, potassium chloride or calcium chloride.

In the process for producing a chlorohydrin according to the invention,the chlorinated agent can be aqueous hydrogen chloride or hydrogenchloride preferentially anhydrous, arising from an installation forproducing allyl chloride and/or an installation for producingchloromethanes and/or an installation of chlorinolysis and/or a hightemperature oxidation installation as described in patent applicationentitled

Process for manufacturing a chlorohydrin by reaction between amulti-hydroxylated aliphatic hydrocarbon and a chlorinating agent” filedin the name of SOLVAY SA on the same day as the present application, thecontent of which is incorporated herein by reference.

Mention is particularly made of a process for manufacturing achlorhydrin from a multi-hydroxylated aliphatic hydrocarbon, an ester ofa multi-hydroxylated aliphatic hydrocarbon, or a mixture thereof, and achlorinating agent, this agent containing at least one of the followingcompounds: nitrogen, oxygen, hydrogen, chlorine, a hydrocarbon, ahalogenated organic compound, an oxygenated organic compound and ametal.

Mention is particularly made of a hydrocarbon selected from aromatichydrocarbons, saturated and unsaturated aliphatic hydrocarbons, ormixtures thereof.

Mention is particularly made of an aliphatic unsaturated hydrocarbonselected from acetylene, ethylene, propylene, butene, propadiene,methylacetylene, and mixtures thereof, of a saturated hydrocarbonselected from methane, ethane, propane, butane and mixture thereof, andof an aromatic hydrocarbon which is benzene.

Mention is particularly made of a halogenated organic compound which isa chlorinated organic compound selected from chloromethanes,chloroethanes, chloropropanes, lchlorobutanes, vinyl chloride,vinylidene chloride, monochloropropenes, le perchloroethylene,trichlorethylene, chlorobutadiene, lchlorobenzenes and mixture thereof.

Mention is particularly made of a halogenated organic compound which isa fluorinated organic compound selected from fluoromethanes,fluoroethanes, vinyl fluoride, vinylidene fluoride and mixtures thereof.

Mention is particularly made an oxygenated organic compound which isselected from alcohols, chloroalcohols, chlorethers and mixturesthereof.

Mention is particularly made of a metal selected from alkaline metals,alkaline-earth metals, iron, nickel, copper, lead, arsenic, cobalt,titanium, cadmium, antimony, mercury, zinc, selenium, aluminium, bismuthand mixtures thereof.

Mention is more particularly made of a process in which the chlorinatingagent est issued at least partially from a process for manufacturingallyl chloride and/or from a process for manufacturing chloormethanesand/or from a chlorinolysis process and/or from a process for oxidizingchlorinated compounds at a temperature higher than or equal to 800° C.

In a more preferred embodiment, the chlorinating agent does not containgaseous hydrogen chloride.

The process for producing a chlorohydrin according to the invention canbe carried out in a reactor as specifically disclosed in the patentapplication WO 2005/054167 of SOLVAY SA from page 6, lines 3 to 23.

Mention is particularly made of an installation made of, or coated with,materials resisting to chlorinating agents, in particular to hydrogenchloride, under the reaction conditions. Mention is more particularlymade of an installation made of enamelled-steel or of tantalum.

The process for producing a chlorohydrin according to the invention canbe carried out in equipments, made of or coated with, materials that areresistant to chlorinating agents, as described in patent applicationentitled <<Process for manufacturing a chlorohydrin in equipmentsresisting to corrosion” filed under the name of SOLVAY SA on the sameday of the present application, the content of which is hereinincorporated by reference.

Mention is particularly made of a process for manufacturing achlorhydrin comprising a stage in which a multi-hydroxylated aliphatichydrocarbon, an ester of a multi-hydroxylated aliphatic hydrocarbon, ora mixture thereof, is submitted to a reaction with a chlorinating agentcontaining hydrogen chloride and at least one other stage carried out inan equipment, made of or covered with, materials resisting to thechlorinating agent under the conditions of theis stage. Mention is moreparticularly made of metallic materials such as enamelled-steel, goldand tantalum and of non-metallic materials such as high densitypolyethylene, polypropylene, poly(vinylidene fluoride),polytetrafluoroethylene, perfluoro alkoxyalcanes andpoly(perfluoropropylvinylether), polysulfones and polysulfides, graphiteet impregnated graphite.

The process for producing a chlorohydrin according to the invention canbe carried out in a reaction mixture as described in patent applicationentitled

Continuous process for the manufacture of chlorohydrins” filed under thename of SOLVAY SA on the same day as the present application, thecontent of which is herein incorporated by reference.

Mention is particularly made of a continuous process for manufacturing achlorhydrin, wherein a multi-hydroxylated aliphatic hydrocarbon, anester of a multi-hydroxylated aliphatic hydrocarbon, or a mixturethereof, is submitted to a reaction with a chlorinating agent and anorganic acid in a liquid reaction medium which composition at thestationnary state comprises the multi-hydroxylated aliphatic hydrocarbonand esters of the multi-hydroxylated aliphatic hydrocarbon, the sum ofthe contents of the multi-hydroxylated aliphatic hydrocarbon and estersof the multi-hydroxylated aliphatic hydrocarbon being higher than orequel to 1.1 mol % and lower than or equal to 30 mol %, the percentagebeing expressed with respect to the organic part of the liquid reactionmedium.

The organic part of the liquid reaction medium is defined as the sum ofthe organic compounds of the liquid reaction medium that is to saycompounds which molecule contents at least one carbon atom.

In the process for producing a chlorohydrin according to the invention,the reaction between the multihydroxylated-aliphatic hydrocarbon, theester of a multihydroxylated-aliphatic hydrocarbon, or the mixturethereof, and the chlorinating agent can be carried out in the presenceof a catalyst, as specifically disclosed in the patent application WO2005/054167 of SOLVAY SA from page 6, line 28 to page 8, line 5. Mentionis particularly made of a catalyst which is a carboxylic acid or acarboxylic acid derivative having an atmospheric boiling point ofgreater than or equal to 200° C., preferably adipic acid or an adipicacid derivative.

In the process for producing a chlorohydrin according to the invention,the reaction between multihydroxylated-aliphatic hydrocarbon, the esterof a multihydroxylated-aliphatic hydrocarbon, or the mixture thereof andthe chlorinating agent can be carried out at a temperature, a pressureand a residence time as specifically disclosed in the patent applicationWO 2005/054167 of SOLVAY SA from page 8, line 6 to page 10, line 10.

Mention is particularly made of a temperature of at least 20° C. and atmost 160° C., of a pressure of at least 0.3 bar and at most 100 bar, andof a residence time of at least 1 h and at most 50 h.

In the process for producing a chlorohydrin according to the invention,the reaction between the multihydroxylated-aliphatic hydrocarbon, theester of a multihydroxylated-aliphatic hydrocarbon, or the mixturethereof, and the chlorinating agent can be carried out in a solvent asspecifically disclosed in the patent application WO 2005/054167 ofSOLVAY SA from page 11, line 12 to 36.

Mention is particurlarly made of an organic solvent such as achlorinated organic solvent, an alcohol, a ketone, an ester or an ether,a non-aqueous solvent not miscible with the multi-hydroxylated aliphatichydrocarbon such as chloroethanol, chloropropanol, chlorpropanediol,dichloropropanol, dioxane, phenol, cresol and mixtures ofchloropropanediol and dichloropropanol, or havy products from thereaction such as oligomers of the multi-hydroxylated aliphatichydrocarbon at least partially chlorinated and/or esterified.

In the process for producing a chlorohydrin according to the invention,the reaction between the multihydroxylated-aliphatic hydrocarbon, theester of a multihydroxylated-aliphatic hydrocarbon, or the mixturethereof, and the chlorinating agent can be carried out in the presenceof a liquid phase comprising heavy compounds as described in patentapplication entitled

Process for manufacturing a chlorohydrin in a liquid phase” filed underthe name of SOLVAY SA on the same day as the present application, thecontent of which is herein incorporated by reference.

Mention is particularly made of a process for manufacturing achlorhydrin in which a multi-hydroxylated aliphatic hydrocarbon, anester of a multi-hydroxylated aliphatic hydrocarbon, or a mixturethereof, is submitted to a reaction with a chlorinating agent, in thepresence of a liquid phase comprising heavy compounds which boilingtemperature under 1 bar of absolute pressure is at least 15° C. higherthan the boiling point of the chlorohydrin under 1 bar of absolutepressure.

The process for producing a chlorohydrin according to the invention canbe carried under batch mode or continuous mode. Continuous mode ispreferred.

In the process for producing a chlorohydrin according to the invention,the reaction between the multihydroxylated-aliphatic hydrocarbon, theester of a multihydroxylated-aliphatic hydrocarbon, or the mixturethereof, and the chlorinating agent is preferably carried out in aliquid reaction medium. The liquid reaction medium can be mono- ormultiphases.

The liquid reaction medium is made up of all of the dissolved ordispersed solid compounds, dissolved or dispersed gas, dissolved ordispersed liquids, at the temperature of the reaction.

The reaction medium comprises the reactants, the catalyst, the solvent,the impurities present in the reactants, in the catalyst and in thesolvent, the intermediates, the products and the by products of thereaction.

By reactants, one intends to denote the multihydroxylated-aliphatichydrocarbon, the ester of a multihydroxylated aliphatic hydrocarbon andthe chlorinating agent.

Among the impurities present in the multihydroxylated-aliphatichydrocarbon, one can mention carboxylic acids, carboxylic acid salts,esters of fatty acids with the multihydroxylated-aliphatic hydrocarbon,esters of fatty acids with alcohols used during trans-esterification,inorganic salts such as for example, alkaline and alkaline-earthchlorides and sulfates.

When the multihydroxylated-aliphatic hydrocarbon is glycerol, one canmention among the impurities of glycerol, carboxylic acids, carboxylicacid salts, fatty acid esters such as mono-, di- and triglycerides,esters of fatty acids with alcohols used during trans-esterification,inorganic salts such as for example, alkaline and alkaline-earthchlorides and sulfates.

Among intermediates, one can mention monochlorohydrins of themultihydroxylated-aliphatic hydrocarbon, their esters and/or polyesters,esters and/or polyesters of the multihydroxylated-aliphatic hydrocarbonand esters of polychlorohydrins.

When the chlorohydrin is dichloropropanol, one can mention amongintermediates, the monochlorohydrin of glycerol and its esters and/orpolyesters, esters and/or polyesters of glycerol and esters ofdichloropropanol.

The ester of multihydroxylated aliphatic hydrocarbon can then be areactant, an impurity of the multihydroxylated aliphatic hydrocarbon oran intermediate.

By products, one intends to denote the chlorohydrin and water. Water canbe the water produced by the chlorination reaction and/or waterintroduced in the process.

Among by-products, one can mention for example, oligomers of themultihydroxylated-aliphatic hydrocarbon, partially chlorinated and/oresterified.

When the multihydroxylated-aliphatic hydrocarbon is glycerol, amongby-products, one can mention, glycerol oligomers, partially chlorinatedand/or esterified.

Intermediates and by-products can be formed in the various steps of theprocess, for example, during the manufacture of the chlorohydrin orduring the separation steps of the chlorohydrin.

The liquid reaction medium can then contain themultihydroxylated-aliphatic hydrocarbon, the chlorination agentdissolved or dispersed in the form of bubbles, the catalyst, thesolvent, the impurities present in the reactant, the catalyst and thesolvent, such as salts dissolved or solid for instance, intermediates,products and by-products of the reaction.

In the process according to the invention, the separation of thechlorohydrin from the other compounds of the reaction medium can becarried out as disclosed in the patent application WO 2005/054167 ofSOLVAY SA from page 12, line 1 to page 16, line 35 and at page 18, lines6 to 13. These other compounds are those already mentioned and comprisenon-consumed reactants, impurities present in the reactants, in thecatalyst and in the solvent, the catalyst, the solvent, theintermediates, water and the by-products of the reaction.

In the process according to the invention, separation and treatment ofthe other compounds of the reaction medium can be carried out asdescribed in the patent application WO 2005/054167 of SOLVAY SA frompage 18, lines 6 to 13.

Mention is particularly made of a separation by azeotropic distillationof a water/chlorhydrin/chlorinating agent mixture in conditionsminimizing losses of the chlorinating agent followed by a separation ofthe chlorohydrin by decantation.

In the process for manufacturing the chlorhydrin according to theinvention, the separation of the chlorohydrin from the other compoundsof the reaction medium can be carried out as described in the patentapplication entitled

Process for manufacturing a chlorohydrin

filed under the name of SOLVAY SA, on the same day as the presentapplication, and the content of which is herein incorporated byreference.

Mention is particularly made of a process for manufacturing achlorohydrin comprising the following steps: (a) a multi-hydroxylatedaliphatic hydrocarbon, an ester of a multi-hydroxylated aliphatichydrocarbon, or a mixture thereof, is submitted to a reaction with achlorinating agent and an organic acid in order to obtain a mixturecontaining the chlorhydrin and esters of the chlorohydrin, (b) at leasta part of the mixture obtained in step (a) is submitted to one or moretreatments in steps subsequent to step (a) and (c) themulti-hydroxylated aliphatic hydrocarbon is added to at least one of thesteps subsequent to step (a), so that to react at a temperature of atleast 20° C., with the chlorohydrin esters in order to form at leastpartially esters of the multi-hydroxylated aliphatic hydrocarbon.Mention is more particularly made of a process in which themulti-hydroxylated aliphatic hydrocarbon is glycerol and thechlorohydrin is dichloropropanol.

In the process for manufacturing the chlorhydrin according to theinvention, the separation of the chlorohydrin from the other compoundsof the reaction medium can be carried out as described in the patentapplication entitled

Process for manufacturing a chlorohydrin from a multi-hydroxylatedaliphatic hydrocarbon” filed in the name of SOLVAY SA on the same day asthe present application, and the content of which is herein incorporatedby reference.

Mention is particularly made of a process for manufacturing chlorohydrinby reaction between a multi-hydroxylated aliphatic hydrocarbon, an esterof a multi-hydroxylated aliphatic hydrocarbon, or a mixture thereof, anda chlorinating agent in a reactor which is fed with one or more liquidflows containing less than 50% by weight of the multi-hydroxylatedaliphatic hydrocarbon, the ester of a multi-hydroxylated aliphatichydrocarbon, or the mixture thereof, with respect to the weight of thetotality of the liquid flows introduced in the reactor. Mention is moreparticularly made of a process comprising the following steps: (a) amulti-hydroxylated aliphatic hydrocarbon, an ester of amulti-hydroxylated aliphatic hydrocarbon, or a mixture thereof, isreacted with a chlorinating agent in order to obtain at least one mediumcontaining the chlorhydrin, water and the chlorination agent, (b) atleast one fraction of the medium obtained in step (a) is withdrawn and(c) the fraction withdrawn at step (b) is submitted to a distillationand/or a stripping operation in which multi-hydroxylated aliphatichydrocarbon is added in order to separate from the fraction withdrawn atstep (b) a mixture containing water and the chlorohydrin exhibiting achlorinating agent reduced content compared to the chlorinated agentcontent in the fraction withdrawn at step (b).

In the process for manufacturing the chlorhydrin according to theinvention, the separation of the chlorohydrin from the other compoundsof the reaction medium can be carried out as described in the patentapplication entitled

Process for converting multi-hydroxylated aliphatic hydrocarbons intochlrohydrins” filed under the name of SOLVAY SA, on the same day of thepresent application and the content of which is herein incorporated byreference.

Mention is particularly made of a process for manufacturing achlorohydrin comprising the following steps: (a) a multi-hydroxylatedaliphatic hydrocarbon, an ester of a multi-hydroxylated aliphatichydrocarbon, or a mixture thereof, is reacted with a chlorinating agentin order to obtain a mixture containing chlorhydrin, chlorohydrin estersand water, (b) at least one fraction of the mixture obtained in step (a)is submitted to a distillation and/or stripping treatment in order toobtain a part concentrated in water, chlorohydrin and chlorhydrinesters, and (c) at least one fraction of the part obtained in step (b)is submitted to a separation operation in the presence of at least oneadditive so as to obtain a portion concentrated in chlorhydrin andchlorohydrin esters, and which contains less than 40% by weight ofwater. The separation operation is more particularly a decantation.

In the process according to the invention, separation and treatment ofthe other compounds of the reaction medium can be carried out asdescribed in the patent application entitled <<Process for manufacturinga chlorohydrin by chlorination of a multi-hydroxylated aliphatichydrocarbon” filed in the name of SOLVAY SA on the same day as thepresent application, the content of which is incorporated herein byreference. A preferred treatment can consist of submitting a fraction ofthe other products to a high temperature oxidation.

Mention is particularly made of a process for manufacturing achlorohydrin comprising the following steps: (a) a multi-hydroxylatedaliphatic hydrocarbon, an ester of a multi-hydroxylated aliphatichydrocarbon, or a mixture thereof, the alkaline and/or alkaline-earthmetals content of which is lower than or equal to 5 g/kg, is reactedwith a chlorinating agent and an organic acid, so as to obtain a mixturecontaining at least the chlorohydrin and by-products, (b) at least onepart of the mixture obtained at step (a) is submitted to one or moretreatments in steps subsequent to step (a) and (c) at least one stepsubsequent to step (a) is an oxidation at a temperature higher than orequal to 800° C. Mention is more particularly made of a process in whichin the subsequent step, a part of the mixture obtained at step (a) iswithdrawn and that part is submitted to an oxidation at a temperaturehigher than or equal to 800° C., during the withdrawal. Mention is alsomade of a process in which the treatment of step (b) is a separationoperation selected from the operations of decantation, filtration,centrifugation, extraction, washing, evaporation, stripping,distillation, adsorption or the combination of at least two of them.

In the process for producing a chlorohydrin according to the invention,vapour stripping, in particular steam stripping of the reaction medium,can be carried out. The reaction medium is defined as above. This mediumis preferably a liquid reaction medium (a liquid phase) as definedabove. When the reaction medium is a liquid phase, the expression“reaction medium” also includes the gas phase in equilibrium with theliquid. In the following, the expression “reaction medium” will then beused to designate indistinctly the liquid phase where the reactionbetween the multihydroxylated-aliphatic hydrocarbon and the chlorinatingagent occurs and the gas phase in equilibrium with that liquid phase.When vapour stripping of the reaction medium is carried out, it ispossible to obtain a stripped fraction containing from 1 to 5, sometimes from 2 to 3 and preferably from 1.5 to 2.5 mol/l of chlorinatedorganic compound, in particular of chlorohydrin. The stripped fractionis mainly composed of water and the chlorohydrin.

In the process for producing a chlorohydrin according to the invention,when the chlorohydrin is not completely removed from the reactionmixture by withdrawal of a fraction containing water, it is possible torecover at least another fraction of the reaction mixture containing thechlorohydrin.

In this aspect of the process for producing a chlorohydrin according tothe invention, at least one fraction comprising from 50 to 95% by weightof the chlorohydrin and at most 50% by weight of water is generallyrecovered. Preferably, this fraction comprises from 75 to 99.9%, oftenfrom 75 to 99%, by weight of the chlorohydrin and from 0.01 to 25%,often from 1 to 25%, by weight of water.

The recovery is preferably carried out by distillation or evaporation.Other fractions obtained during this step, comprising, for example,intermediates and, optionally, the multihydroxylated-aliphatichydrocarbon and the catalyst, can be recycled to the reaction with thechlorinating agent. It is also possible to separate at least onefraction containing heavy by-products of the reaction, such as describedin the patent application WO 2005/054167 of SOLVAY SA from page 11, line32 to page 11, line 34, in particular chlorinated polymers of themultihydroxylated-aliphatic hydrocarbon, which can be destroyed or canoptionally be used in a process for producing polymers of themultihydroxylated-aliphatic hydrocarbon, for example by dechlorination.

The distillation or evaporation is generally carried out at atemperature of at least 20° C. This temperature is often at least 60° C.It is preferably at least 70° C. The distillation or evaporation isgenerally carried out a temperature of at most 180° C. This temperatureis preferably at most 140° C.

The distillation or evaporation is generally carried out at a pressureof greater than 0.001 bar. This pressure is preferably greater than orequal to approximately 0.003 bar. The distillation or evaporation isgenerally carried out at a pressure of at most 15 bar. This pressure isoften at most 10 bar. It is preferably at most 7 bar, more preferably atmost 1 bar, yet more preferably at most 0.5 bar and most preferably atmost 0.1 bar.

The distillation or evaporation operation can be carried out either bymeans of distillation columns or by means of evaporators, of filmevaporators or alternatively of wiped thin film evaporators.

The recoverable fractions of the residues can be separated there from byphysical and/or chemical operations. An example of physical operation isa distillation advantageously by means of a wiped thin film evaporatorwith an interior or exterior condenser. An example of a chemicaloperation is an hydrolysis of the residue to recover for instance thecatalyst.

In a particular variant of the process of the invention, when thechlorohydrin is a dichlorohydrin, the dichlorohydrin is producedaccording to a process comprising:

-   (a) a first reaction step in which a multihydroxylated-aliphatic    hydrocarbon is brought into contact with the chlorinating agent so    as to obtain a fraction of products comprising at least a    monochlorohydrin;-   (b) optionally at least part of the fraction of products is    subjected to a drying operation;-   (c) at least part of the fraction of optionally dried products is    introduced into a second reaction step in which at least part of the    monochlorohydrin is reacted with the chlorinating agent.

Steps (a) and (c) in this variant are preferably carried out underconditions and with the preferences as described above for the processfor producing the chlorohydrin according to the invention. However, itis preferred to carry out the reaction of step (a) in the presence ofwater at a concentration preferably ranging from 3 to 40% by weight,preferably from 3 to 40% by weight relative to the total weight of thereaction medium.

Step (b) can be carried out, for example, by a stripping operation in atleast one of the reactors of steps (a) or (c) or by means of anevaporator placed on a recirculation pipe exterior to the reactor or bydistillation. According to another preferred variant, the water isremoved by means of a membrane technique.

The process for producing a chlorohydrin according to the invention canbe carried out, for example, in cascade reactors, in at least one platecolumn or in at least one bubble column, or an assembly of suchreactors.

The reactors may effectively be of a type that is stirred either bymeans of internal stirring, or by means of a recirculation pipe exteriorto the reactor.

When, in the process according to the invention, the reaction medium isheated, the heating can be obtained, for example, by means of a jacketor by means of an internal heat exchanger. Heating can also be obtainedby means of a heat exchanger on a recirculation pipe exterior to thereactor. Optionally, the heating is obtained by combined use of a jacketand of a heat exchanger on a recirculation pipe exterior to the reactor.

In particular when the process according to the invention is operated ina continuous or fed-batch mode, secondary reactions can lead to thebuild-up in the reactor of by-products of low volatility, among whichmore or less chlorinated oligomers of the multihydroxylated-aliphatichydrocarbon. This build-up can lead to a progressive increase of thevolume of the reaction medium, to a progressive loss of productivity andrequire a continuous or discontinuous purge of the reactor to keep thevolume at an adequate level. By the expression “purge”, one intends todenote a withdrawal of a fraction of the reaction medium.

If appropriate, the catalyst quantity which is removed during suchpurging operation can be compensated by the introduction of anequivalent quantity of pure or purified catalyst.

The catalyst contained in the purge from the reaction mixture can beeconomically recycled in the reactor after a purification treatment. Forexample, catalysts with low solubility in water can be subjected to anacid hydrolysis treatment, preferably carried out at a temperaturehigher than 30° C., preferably at least 50° C. which is followed by aseparation step e.g. by decantation, filtration or extraction. It hasbeen found that in the case of adipic acid, an acid hydrolysis of thepurge leads after cooling and filtration, to the recovery ofcrystallised adipic acid of high purity with a good yield.

In particular when the process according to the invention is operated ina continuous or fed-batch mode, metal salts, in particular NaCl,optionally present in the raw materials, for example in themultihydroxylated-aliphatic hydrocarbon, the ester of amultihydroxylated-aliphatic hydrocarbon, or the mixture thereof, fromrenewable resources described above, can concentrate in the reactorwhere the reaction between the multihydroxylated-aliphatic hydrocarbon,the ester of a multihydroxylated-aliphatic hydrocarbon, or the mixturethereof, and the chlorinating agent is carried out. An increase of metalsalt content could possibly lead to a progressive crystallisation ofinsoluble materials, leading to an increase of the volume of thereaction mixture and to various problems linked to the presence of solidmaterials such as deposit formation on the reactor walls, on the stirrerand on feed and purge lines and valves. Deposit formation on the reactorwall can reduce the heat transfer efficiency and require an increaseamount of energy to maintain the temperature of the reaction mixture.Deposit formation on valves and lines can lead to plugging problems. Anincreased amount of solid in the reaction mixture can reduce thestirring efficiency and require a higher amount of energy to reach acorrect agitation. Increase of metal salt concentration could thenrequire a higher continuous or discontinuous purge rate leading tohigher losses of products.

While the presence of metal salt is surprisingly acceptable in theprocess according to the invention, it may therefore be desirable toremove at least part of the metal salt, in particular NaCl, from thereaction system, e.g. in order to prevent optional accumulation of metalsalt in the reaction mixture. Such removal can suitably be carried outby subjecting at least a fraction of the reaction mixture which containsmetal salt, solid or dissolved, to a treatment comprising at least oneseparation operation to remove at least part of the metal salt from saidfraction.

The separation operation can be selected from liquid/solid,liquid/liquid, liquid/gas and solid/gas separations.

The liquid/solid separation operation can be selected from decantation,centrifugation, filtration, adsorption and treatment with ion-exchangedresins. The liquid/liquid separation operation can be selected fromdecantation and centrifugation. The liquid/gas separation operation canbe selected from stripping, evaporation and distillation.

Liquid/solid separation operations are preferred, filtration is morepreferred and filtration where the metal is removed as a solid is mostpreferred.

In the process according to the invention, the reaction is preferablycarried out in a reaction mixture and the separation operation iscarried out on at least a fraction of the reaction mixture. The fractionof the reaction mixture can be submitted to a treatment to remove atleast one component other than the metal salt prior to the separationoperation. That treatment can be a stripping or a distillationoperation;

The fraction of the reaction mixture to be submitted to the separationoperation can be directly withdrawn from the reaction mixture, notablywhen the reaction is carried out in the liquid phase. The fraction ofthe reaction mixture to be submitted to the separation operation canalso be withdrawn from the reaction mixture and further treated beforeremoving the metal salt. An example of a suitable treatment is aconcentration operation carried out on a liquid fraction of the reactionmixture wherein volatile compounds such as starting materials andproducts of the reaction, which may optionally be recovered and/orrecycled to the reaction mixture, are separated e.g. by stripping,distillation or evaporation and a concentrated fraction having increasedcontent of metal salt, solid or dissolved, is obtained and subjected tothe treatment to separate metal salt.

The separation step can then be carried out at any step of the processfor producing the chlorohydrin as described in the patent application WO2005/054167 of SOLVAY SA from page 12, line 1 to page 18, line 13, forinstance after the chlorination reaction, after the step of removing amixture of the chlorhydrin and water from the reaction mixture, afterthe recovery of chlorohydrin by distillation or evaporation, after thepurge of by-products of reaction or after the treatment for recoveringthe catalyst from the purge.

In a preferred embodiment, the fraction of the reaction mixture whichcontains metal salt is obtained from the purge of the reactor where thereaction takes place and is sent to a least one separation unit, wherethe separation of the metal salt is carried out for example byadsorption, distillation, extraction, decantation, centrifugation,filtration and treatment with ion exchanged resins. A liquid/solidseparation unit is preferred and a separation by filtration is morepreferred. The separated liquid is preferably recycled back to thereactor and the metal salt is left on the filter.

The filtration step can be carried out at a temperature which is usuallygreater than or equal to 4° C., preferably greater than or equal to 20°C., more preferably greater than or equal to 30° C., yet more preferablygreater than or equal to 50° C. and most preferably greater than orequal to 80° C. This temperature is generally lower than or equal to150° C. and preferably lower than or equal to 140° C.

The nature of the filtration system is not critical and is readilyapparent to the skilled person aware of the present invention. Adescription of suitable filtration systems can be found in “Perry'sChemical Engineers' Handbook, Sixth Edition, 1984, Sections 19-65 to19-103”.

As the metal salt accumulates on the filtration system, it is generallyrecommended to periodically regenerate the filtration unit by removingthe filtrated salt. The regeneration can be performed by any means, forexample by removing, in particular by mechanical means, the solid or bydissolving the solid. Optionally, solid elution treatments can beincorporated in the regeneration procedure.

In a one embodiment according to the invention, the metal salt isremoved as a solid from the filtration system without any pretreatment.

In a first variant, the salt is disposed off in a suitable mannerwithout further treatment.

In a second variant, the salt is stored in a separate vessel for furthertreatment. Further treatment can include elution of the solid withsolvents and dissolution of the solid with solvents. Such treatments aredescribed herebelow in the preferred embodiment.

In a preferred embodiment according to the invention, the metal salt istreated before removal from the filtration system.

Optionally adsorbed products and reactants such as in particularcatalyst and chlorohydrins and their esters can be recovered from themetal salts, in particular from NaCl, for example by elution with anappropriate eluting solvent such as a mixture of water and thechlorohydrin. Any ratio between water and the chlorohydrin is suitable.It is preferred to use the chlorohydrin saturated with water at roomtemperature. It is particularly preferred to use one of the phaseobtained from the decantation between the chlorohydrin and water. Thewater content of the chlorohydrin used as eluting solvent is generallylower than or equal to 20% by weight and preferably lower than or equalto 15% and most preferably lower than or equal to about 12%. The watercontent in the mixture of water and the chlorohydrin is generally higherthan or equal to 1% by weight.

In another embodiment, the eluting solvent consists essentially of thechlorohydrin. In this embodiment, the water content is generally lowerthan 1% by weight, preferably lower than or equal to 0.5% by weight.

In still another embodiment, the eluting solvent is water for examplefresh water as defined above.

The elution step can be carried out at a temperature which is usuallygreater than or equal to 20° C., preferably greater than or equal to 50°C. and most preferably greater than or equal to 80° C. This temperatureis generally lower than or equal to 150° C. and preferably lower than orequal to 140° C.

After elution, the solvent used for eluting the metal salt can berecycled to the chlorination reactor.

Several steps of elution can be performed.

In particular after elution with the chlorohydrin the metal salt canthen be optionally further eluted with an aqueous solution. The aqueoussolution can arise from any step of the process. It is preferred to usefresh water as defined below.

The elution step can be carried out at a temperature which is usuallygreater than or equal to 20° C., preferably greater than or equal to 50°C. and most preferably greater than or equal to 80° C. This temperatureis generally lower than or equal to 150° C. and preferably lower than orequal to 140° C.

After elution, the aqueous solution used for eluting the metal salt canbe sent to the chlorination reactor, to a dehydrochlorination unit, to abiological treatment unit or to an oxidation treatment unit.

In a first variant, after elution with the chlorohydrin and water, thesalt is removed as a solid in a suitable manner without furthertreatment. The salt is then disposed off in a suitable manner.

In a second variant, after elution with the chlorohydrin and water, thesalt is dissolved with an aqueous solution.

The aqueous solution can arise from any step of the process. It ispreferred to use fresh water as defined above.

The dissolution step can be carried out at a temperature which isusually greater than or equal to 20° C., preferably greater than orequal to 50° C. and most preferably greater than or equal to 80° C. Thistemperature is generally lower than or equal to 150° C. and preferablylower than or equal to 140° C.

The aqueous solution containing the dissolved metal salt can be disposedoff. Preferably, it is sent to a dehydrochlorination unit, to abiological treatment unit or to an oxidation treatment unit.

In the above variants, the elution of the metal salt with water and thedissolution of the metal salt with water can be part of a single unitoperation.

The above operations are particularly suited when the metal salt issodium chloride or potassium chloride or sodium sulfate or potassiumsulfate or any of their mixtures and more particularly suited for sodiumchloride.

When the purge is carried out in a discontinuous mode, one filtrationunit is usually sufficient since the filtration system can beregenerated during the shut-downs of the purge. When the purge iscarried out in a continuous mode, it is preferred to have at least twofiltration units working in alternance, one being in filtration modewhile the other is in regeneration mode.

The filtration operation can be carried out in batch mode or continuousmode.

When anhydrous HCl is used as chlorinating agent, it is preferred todirect a liquid stream comprising the multihydroxylated-aliphatichydrocarbon against the current of the stream of HCl. When the processis carried out in several reactors, the HCl is advantageously driedbetween two reactors, for example by adsorption on a suitable solid,such as a molecular sieve, or by reverse osmosis through a suitablemembrane.

This particular embodiment of the process according to the inventionmakes it possible to obtain, particularly economically, a concentratedchlorhydrin often having a chlorohydrin content of greater than or equalto 90° A) by weight relative to the total weight of the chlorohydrin.When the chlorohydrin is dichloropropanol, by means of this approach, itis possible to obtain 1,3-dichloropropane-2-ol as major isomer with anisomeric purity of greater than 80%.

In the process according to the invention, the mixture can contain the1,3-dichloropropane-2-ol: and 2,3-dichloropropane-1-ol isomers in a massratio 1,3-dichloropropane-2-ol:2,3-dichloropropane-1-ol generally higherthan or equal to 0.5, often higher than or equal to 3, frequently higherthan or equal to 7 and in particular higher than or equal to 20.

The invention is also related to a process for producing a chlorohydrin,according to which:

-   (a) a multihydroxylated-aliphatic hydrocarbon, anester of a    multihydroxylated-aliphatic hydrocarbon, or a mixture thereof, is    subjected to a reaction with a chlorinating agent in a reaction    medium-   (b) continuous or periodic withdrawal from the reaction medium of a    fraction comprising at least water and the chlorohydrin, is carried    out-   (c) at least part of the fraction obtained in step (b) is introduced    into a distillation step-   (d) the reflux ratio of the distillation step is controlled by    supplying water to said distillation step.

The reaction medium is defined as above.

The fraction withdrawn at step (b) has a water content preferably higherthan or equal to 12% by weight relative to the total weight of thewithdrawn fraction.

The fraction withdrawn at step (b) may also contain hydrogen chloride.Preferably, the fraction is withdrawn continuously as its constituentsform. The fraction obtained can subsequently be subjected to anoperation of decantation after the distillation step.

The reaction medium of step (a) can be fed with water, in particularwith steam. The feeding can be effected with extrinsic water originatingfrom a suitable feed pipe or, optionally, with residual water recoveredfrom another unit reaction or operation.

This feed is generally effected in such as way as to maintain the waterconcentration in the reaction medium within the ranges as described inpatent application WO 2005/054167 in the name of SOLVAY SA from page 10,line 31 to page 11, line 11.

Continuous or periodic withdrawal can be carried out by introducing intoa distillation step a gaseous phase, in particular withdrawing andintroducing into a distillation step a gas phase which is in equilibriumwith a liquid phase. A particular embodiment for the process accordingto the invention is to carry out steps (a) to (d) in a reactorsurmounted by a suitable distillation column. Step (a) is carried out inthe reactor. This embodiment is particularly suitable when aqueoushydrochloric acid is used as chlorinating agent. It is most particularlysuitable when the chlorinating agent does not contain gaseous hydrogenchloride. In another embodiment for the process according to theinvention, it is also possible to arrange a distillation columnseparated from the reactor, the liquid bottom of which can be sent backto the reaction medium. This embodiment is particularly suitable whenhydrogen chloride, for example gaseous or essentially anhydrous hydrogenchloride, is used as chlorinating agent. Anhydrous hydrogen chloride hasa water content which is generally lower than or equal to 40% by weight,preferably lower than or equal to 30% by weight and most preferablylower than or equal to 25% by weight. The water content of anhydroushydrogen chloride is generally higher than or equal to 1 ppm by weight.

In one aspect, the fraction to be introduced into the distillationcolumn separated from the reactor is withdrawn continuously orperiodically, preferably continuously, from the liquid reaction mixtureand at least water and the chlorohydrin is separated. In addition, oneor more fractions containing organic products such as heavy byproductsand in particular catalyst and/or hydrogen chloride can also beseparated in this distillation step and generally recycled to thereaction mixture. By selecting an appropriate reflux ratio, it ispossible to separate in this aspect a fraction containing at least waterwhich is substantially free of hydrogen chloride.

The reflux ratio can suitably be adjusted by supplying water which ispreferably substantially free of hydrogen chloride to the distillationcolumn. In this embodiment, the water is preferably fed to the top ofthe distillation column, Water can be supplied, for example by recyclingat least a portion of water separated in the distillation operation tothe top of the distillation column. Water can also be supplied by addingfresh water to the top of the distillation column. Both manners ofsupplying water can be combined. Adding fresh water gives particularlygood results.

“Substantially free of hydrogen chloride”, is understood to denote inparticular a hydrogen chloride content in the fraction comprising waterequal to or less than 10% by weight relative to the total weight of thefraction comprising water. Often, this content is equal to less than 5%by weight and preferably equal to or less than 1% by weight and morepreferably equal to or less than 0.3% by weight. If hydrogen chloride ispresent in the fraction “substantially free of hydrogen chloride”, itscontent is generally equal to or more than 1 mg/kg, often equal to ormore than 5 mg/kg and in particular equal to or more than 10 mg/kgrelative to the total weight of the fraction comprising water.

“Fresh” water is understood to denote water having a content ofconstituents other than water, organic or inorganic, lower than or equalto 12% by weight relative to the total weight of the water and of suchconstituents, preferably lower than or equal to 10% by weight and mostpreferably lower than or equal to 1% by weight. Generally, “fresh” wateris understood to denote in particular water having a content ofconstituents other than water, organic or inorganic, equal to or morethan 0.001 mg/kg, often equal to or more than 1 mg/kg relative to thetotal weight of water and of such constituents and frequently higherthan or equal to 10 mg/kg. A possible source of fresh water can be forexample the water used for eluting metal salt as described herein below,demineralized water obtained from ion-exchange resins, distilled wateror water arising from steam condensation.

By constituents other than water, one intends to designate morespecifically the chlorohydrin.

It has been found that the exploitation of the liquid-vapour equilibriumproperties of the water-hydrogen chloride-chlorohydrin ternarycomposition makes it possible to withdraw from the production reactionthe reaction products comprising in particular the chlorohydrin andwater, while at the same time allowing most of the catalyst(s) and ofthe reactants (including the hydrogen chloride), to be recycled to thereactor, especially when the chlorohydrin is dichloropropanol.

The invention relates then also to a process for producing achlorohydrin, according to which:

-   (a) a multihydroxylated-aliphatic hydrocarbon, an ester of a    multihydroxylated-aliphatic hydrocarbon, or a mixture thereof, is    subjected to a reaction with hydrogen chloride in a reaction mixture-   (b) continuous or periodic withdrawal from the reaction mixture of a    fraction comprising at least water, the chlorhydrin and hydrogen    chloride, is carried out-   (c) at least part of the fraction obtained in step (b) is introduced    into a distillation step    wherein the ratio between the hydrogen chloride concentration and    the water concentration of the fraction introduced into the    distillation step is lower than the hydrogen chloride/water    concentration ratio in the binary azeotropic composition hydrogen    chloride/water at the temperature and pressure of the distillation.

This process is preferably carried out continuously.

In process according to the invention, the operating conditions of thereactor where the reaction between the multihydroxylated-aliphatichydrocarbon, the ester of a multihydroxylated-aliphatic hydrocarbon, orthe mixture thereof, and the chlorinated agent occurs, such as feedrates of reactants, in particular hydrogen chloride and themultihydroxylated-aliphatic hydrocarbon, the ester of amultihydroxylated-aliphatic hydrocarbon, or the mixture thereof,catalyst feed rate, temperature, reactor volume and pressure arepreferably adjusted in such a way that the hydrogen chloride content ofthe fraction introduced into the distillation step is lower than thehydrogen chloride concentration in the binary azeotropic compositionhydrogen chloride/water at the temperature and pressure of thedistillation. An effective means of adjusting this concentration iscontrolling the hydrogen chloride supply to the liquid reaction medium.

It is possible for example to control the hydrogen chloride content inthe fraction of step (b) by adding water. Such addition can be carriedout for example by injection of vapor into the boiler of a distillationcolumn used in the distillation step or by recycling to the distillationstep of a water phase which can be obtained for example by decantationof a fraction withdrawn from the top of a distillation column, or byadding fresh water to the top of a distillation column or by adding amixture of recycled and fresh water.

The maximum suitable hydrogen chloride concentration decreases slightlywhen the operating pressure is higher in agreement with theliquid-vapour equilibrium data for the azeotropic hydrogen chloridepublished by Bonner and Titus (J. Amer. Chem. Soc. 52, 633 (1930)) andpartially reprinted in the Table hereafter:

Pressure Temperature HCl in azeotrope (Torr) (° C.) (% wt ) 50 48.7423.42 250 85.21 21.88 370 90.24 21.37 540 99.65 20.92 760 108.58 20.221000 116.19 19.73 1220 122.98 19.36

In such conditions, a fraction comprising water which fraction issubstantially free of hydrogen chloride as defined above can berecovered by distillation from the reaction mixture or the gas phaseabove the liquid reaction mixture, e.g. by distilling material withdrawnfrom said gas phase and obtaining the fraction comprising waterpreferably at the top of the distillation column.

For instance, when the chlorohydrin is dichloropropanol, at atmosphericpressure (101.3 kPa), it is possible to obtain by distillation of thereactor gas phase a binary azeotropic mixture of water anddichloropropanol containing 23% by weight of dichloropropanol if thehydrogen chloride concentration in the total of the hydrogen chlorideand water concentrations in that gas phase in contact with the reactionmedium is lower than about 20.22% by weight.

In the process for producing the chlorohydrin according to theinvention, the chlorohydrin can contain a high amount of halogenatedketones in particular chloroacetone as described in patent applicationFR 05.05120 of SOLVAY SA filed on May 20, 2005, the content of which isincorporated herein by reference. In the process for producing achlorohydrin according to the invention, the halogenated ketone contentof the chlorohydrin can be decreased by submitting the chlorohydrin toan azeotropic distillation in the presence of water or by submitting thechlorohydrin to a dehydrochlorination treatment, as described in patentapplication FR 05.05120 of SOLVAY SA filed on May 20, 2005.

Mention is particularly made of a process for manufacturing an epoxidein which halogenated ketones are formed as by-products and whichcomprises at least one treatment for the elimination of at least onepart of the formed halogenated ketones. Mentions are more particularlymade of a process for manufacturing an epoxide by dehydrochlorination ofa chlorohydrin where at least a fraction of the chlorohydrin ismanufactured by chlorination of a multi-hydroxylated aliphatichydrocarbon, an ester of a multi-hydroxylated aliphatic hydrocarbon, ora mixture thereof, of a treatment of dehydrochlorination and of atreatment by azeotropic distillation of a mixture water-halogenatedketone, both treatments used in order to eliminate at least a part ofthe formed halogenated ketones and of a process for manufacturingepichlorohydrin in which the halogenated ketone is chloroacetone.

In the process for producing a chlorohydrin according to the invention,when the chlorohydrin is dichloropropanol, a high selectivity for1,3-dichloropropane-2-ol is surprisingly obtained, which isomer isparticularly suitable as starting product for a dehydrochlorination witha view to producing epichlorohydrin.

In the process according to the invention, the chlorohydrin can besubmitted to a dehydrochlorination reaction to produce an epoxide, asdescribed in patent applications WO 2005/054167 and FR 05.05120 in thename of SOLVAY SA

In the process according to the invention, the chlorohydrin can besubmitted to a dehydrochlorination reaction as described in patentapplication entitled <<Process for manufacturing an epoxide from amulti-hydroxylated aliphatic hydrocarbon and a chlorinating agent” filedin the name of SOLVAY SA on the same day as the present application, thecontent of which is incorporated herein by reference.

Mention is particularly made of a process for manufacturing an epoxidewherein a reaction mixture resulting from the reaction of amulti-hydroxylated aliphatic hydrocarbon, an ester of amulti-hydroxylated aliphatic hydrocarbon, or a mixture thereof, and achlorinating agent, the reaction mixture containing less than 10 g ofchlorohydrin per kg of the reaction mixture, is submitted to a furtherchemical reaction without intermediate treatment.

Mention is particularly made of a process for the manufacture of anepoxide comprising the following steps: (a) a multi-hydroxylatedaliphatic hydrocarbon, an ester of a multi-hydroxylated aliphatichydrocarbon, or a mixture thereof, is submitted to a reaction with achlorinating agent and an organic acid in order to form a chlorohydrinand esters of chlorhydrin, in a reaction mixture containing, themulti-hydroxylated aliphatic hydrocarbon, the esters ofmulti-hydroxylated aliphatic hydrocarbon, water, the chlorinating agentand the organic acid, the reaction mixture containing at least 10 g ofchlorohydrin per kg of the reaction mixture (b) at least one fraction ofthe mixture obtained in step, fraction which has the same composition asthe reaction mixture obtained at step (a), is submitted to one or moretreatment in steps subsequent to step (a), and (c) a basic compound isadded at least one of the step subsequent to step (a) so as it reacts atleast partially with the chlorohydrin, the esters of the chlorohydrin,the chlorinating agent and the organic acid in order to form an epoxideand salts.

The process for producing a chlorohydrin according to the invention canbe integrated in a global scheme such as described in patent applicationentitled

Process for manufacturing an epoxide from a chlorohydrin” filed in thename of SOLVAY SA on on the same day as the present application, thecontent of which is incorporated herein by reference.

Mention is particularly made of a process for manufacturing an epoxidecomprising at least one purification step of the formed epoxide, theepoxide being at least partially manufactured by a process ofdehydrochlorination of a chlorhydrin, the chlorohydrin being at leastpartially manufactured by a process of chlorination of amulti-hydroxylated aliphatic hydrocarbon, of an ester of amulti-hydroxylated aliphatic hydrocarbon, or a mixture thereof.

When the chlorhydrin is dichloropropanol, the process of the inventioncan be followed by a manufacture of epichlorhydrin bydehydrochlorination of dicghloropropanol and the when the epoxide isepichlorohydrin, it can usefully be used for manufacturing epoxy resins.

FIG. 1 shows a preferred particular scheme for a plant that can be usedfor carrying out the process for producing a chlorohydrin according tothe invention: A reactor (4) is fed, in a continuous or batch mode, witha multihydroxylated-aliphatic hydrocarbon, an ester of amultihydroxylated-aliphatic hydrocarbon, or a mixture thereof, via line(1) and catalyst via line (2), the feed of the chlorinating agent, iscarried out continuously or in batch-mode via line (3), a distillationcolumn (6) is fed via line (5) with vapour produced from reactor (4), astream is withdrawn from column (6) via line (7) and fed to a condenser(8), the stream from the condenser is fed via line (9) to a decanter(10) in which aqueous and organic phases are separated. A fraction ofthe separated aqueous phase is optionally recycled via line (11) to thetop of the column for maintaining reflux. Fresh water can be added vialine (12) to the top of the column for maintaining reflux. Theproduction of the chlorohydrin is distributed between the organic phasewithdrawn through line (14) and the aqueous phase withdrawn through line(13). The residue from column (6) can be recycled to the reactor vialine (15). Heavy by-products can optionally be removed from the reactorby means of a purge (16) located in the liquid bottom of the reactor. Astream is withdrawn from the purge (16) and fed via line (17) into anevaporator (18) wherein a partial evaporation operation is carried oute.g. by heating or by gas sweeping with nitrogen or steam, the gas phasecontaining most of the chlorinating agent from stream (17) is recycledvia line (19) to the column (6) or via line (20) to the reactor (4), adistillation column or stripping column (22) is fed with the liquidphase arising from the evaporator (18) via line (21), the main fractionof the chlorohydrin is collected from the top of the column (22) throughline (23) and the column residue is fed via line (24) to a filtrationunit (25) in which solid and liquid phases are separated, the liquidphase is recycled via line (26) to the reactor (4). The solid can bewithdrawn from the filtration unit (25) via line (27) as a solid or as asolution. Solvents can be added to the filtration unit (25) via lines(28) and (29) for washing and/or dissolution of the solid and withdrawnfrom line (27). Optionally, a stream is withdrawn from the purge (16)and fed via line (30) into a filtration column (25). The stripper (18)and the distillation column (22) are then bypassed.

Results obtained according to this last scheme (stripper (18) and column(22) bypassed) are detailed in example 1.

The process described above is well suited when themultihydroxylated-aliphatic hydrocarbon is ethylene glycol, propyleneglycol and glycerol, the chlorohydrine is chloroethanol, chloropropanol,chloropropanediol and dichloropropanol and the epoxide is ethyleneoxide, propylene oxide, glycidol and epichlorohydrin and thechlorinating agent is hydrogen chloride, anhydrous or in aqueoussolution. The process is particularly convenient when themultihydroxylated-aliphatic hydrocarbon is glycerol, the chlorohydrin isdichloropropanol and the epoxide is epichlorohydrin.

When the multihydroxylated-aliphatic hydrocarbon is glycerol, thisvariant of the process allows to remove at the top by azeotropy almostall of the water arising from the reaction, from the starting materialsand/or possibly fed in the bottom of the reactor or of the column and toobtain a mixture of dichloropropanols of very high purity, above 99.5%by weight for the sum of the two isomers, with a selectivity related tohydrocarbon chain and hydrogen chloride higher than 99% by weight and toremove the metal salt which can build up in the reactor when crudeglycerol is used in the reaction.

The example below are intended to illustrate the invention without,however, limiting it.

EXAMPLE 1

The numbers in parentheses refer to FIG. 1. The additional equipment inthe schema of FIG. 1, with stripper (18) and column (22) has not beenused in this case.

Reactor (4) has been continuously fed with crude glycerol and a 33% byweight hydrochloric aqueous acid solution with relative flow rates massratios of 2.06. The crude glycerol was a by product of the biodieselproduction and contained 85% of glycerol, 6% of NaCl and 0.5% of organicimpurities (fatty acids and derivatives). The residence time was 16 h,the adipic acid concentration in the reaction medium was 2.5 mol of acidfunctionalities/kg. The reactor has been operated at atmosphericpressure and at 115° C. The reaction mixture has been stripped with ofnitrogen and the generated vapor phase has been treated in thedistillation column (6) via line (5) (FIG. 1). The gas phase removedfrom column (6) has been condensed at 25° C. (8) and decanted in thedecanter (10). Reflux ratio was adjusted to withdraw the entireproduction of dichloropropanol at the top of column by recycling anappropriate amount of the aqueous phase from the decantor. At the outletof the decantor an aqueous phase containing 15.0% of dichloropropanol(13) and an organic phase (14) containing 88% of dichloropropanol wererecovered. The profiles in organic impurities in these phases were notdifferent from those observed when pure glycerol is used in the process.

A slurry from the reactor has been pumped on a 115 micrometer PTFEmembrane filter in the filtration column (25). The salt cake in thefilter has been washed at 20° C. with dichloropropanol saturated withwater. After removal of the liquid phase and draining of the solid, thesalt has been dissolved in water and the salted water phase has beendiscarded. The duration of washing and salt dissolution was about 2hours. A new filtration cycle of the slurry from the reactor has thenbeen operated. The dichloropropanol washing has been recycled to thereactor by continuous feeding. The analysis of the water phase with saltindicated a dichloropropanol:NaCl mass ratio of 1.44 and a small amountof catalyst (less than 10 g/kg). The quantity of dichloropropanol in thesalted water represented 1.6% of the dichloropropanol total production.

The global yield in dichloropropanol was 93%.

The invention claimed is:
 1. A process for producing dichloropropanol,comprising reacting glycerol with a chlorinating agent, wherein thereaction is carried out in a reaction mixture comprising glycerol thathas at least one solid or dissolved metal salt therein in a positiveamount of up to at most 15% by weight, the process further comprisingsubmitting at least a fraction of the reaction mixture to a treatmentcomprising a separation operation to remove at least part of the metalsalt from said fraction.
 2. The process according to claim 1, whereinthe glycerol has at least partially been obtained from renewable rawmaterials.
 3. The process according to claim 1, wherein the metal saltis selected from sodium chloride, potassium chloride, sodium sulfate andpotassium sulfate.
 4. The process according to claim 1 wherein theglycerol has from 0.5 to 15% by weight of metal salt therein.
 5. Theprocess according to claim 1 wherein the chlorinating agent is gaseoushydrogen chloride.
 6. The process according to claim 1 wherein thereaction is carried out in the presence of a catalyst, wherein thecatalyst is a carboxylic acid.
 7. The process according to claim 6wherein the carboxylic acid has an atmospheric boiling point of greaterthan or equal to 200° C.
 8. The process according to claim 1 wherein theseparation operation is selected from liquid/solid, liquid/liquid,liquid/gas and solid/gas separation.
 9. The process according to claim 8wherein the separation operation is selected from liquid/solid,liquid/liquid, and liquid/gas separation, and wherein the liquid/solidseparation operation is selected from decantation, centrifugation,filtration, adsorption and treatment with ion-exchanged resins, theliquid/liquid separation operation is selected from decantation andcentrifugation, and the liquid/gas separation operation is selected fromstripping, evaporation and distillation.
 10. The process according toclaim 9 wherein the separation operation is selected from liquid/solid,the liquid/solid separation operation is filtration, and the metal saltis removed as a solid.
 11. The process according to claim 1 wherein thefraction of the reaction mixture is submitted to a treatment to removeat least one component other than the metal salt prior to the separationoperation, and wherein the treatment is a stripping or a distillationoperation.
 12. The process according to claim 1, carried outcontinuously.
 13. The process according to claim 1, further comprisingmanufacturing epichlorohydrin by dehydrochlorination of thedichloropropanol.
 14. The process according to claim 13, furthercomprising manufacturing an epoxy resin by reacting the epichlorohydrin.15. The process according to claim 1 wherein the glycerol has from 0.5to 7.5% by weight of metal salt therein.
 16. The process according toclaim 1 wherein the glycerol has from 0.5 to 5% by weight of metal salttherein.
 17. The process according to claim 1 wherein the glycerol hasfrom 3 to 7.5% by weight of metal salt therein.
 18. The processaccording to claim 1 wherein the glycerol has from 3 to 5% by weight ofmetal salt therein.